The burst of electrophysiological signals in the suprachiasmatic nucleus of mouse during the arousal detected by microelectrode arrays

Yiding Wang; Yilin Song; Yuchuan Dai; Xinrong Li; Jingyu Xie; Jinping Luo; Chao Yang; Penghui Fan; Guihua Xiao; Yan Luo; Ying Wang; Yinghui Li; Xinxia Cai

doi:10.3389/fbioe.2022.970726

The burst of electrophysiological signals in the suprachiasmatic nucleus of mouse during the arousal detected by microelectrode arrays

Front Bioeng Biotechnol. 2022 Aug 30:10:970726. doi: 10.3389/fbioe.2022.970726. eCollection 2022.

Authors

Yiding Wang^{1

2}, Yilin Song^{1

2}, Yuchuan Dai^{1

2}, Xinrong Li^{1

2}, Jingyu Xie^{1

2}, Jinping Luo^{1

2}, Chao Yang³, Penghui Fan^{1

2}, Guihua Xiao^{1

2}, Yan Luo⁴, Ying Wang⁴, Yinghui Li³, Xinxia Cai^{1

2}

Affiliations

¹ State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing, China.
² School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing, China.
³ China Astronaut Research and Training Center, Beijing, China.
⁴ Department of Anesthesiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China.

Abstract

The neural mechanisms of torpor have essential reference significance for medical methods and long-term manned space. Changes in electrophysiology of suprachiasmatic nucleus (SCN) conduce to revealing the neural mechanisms from the torpor to arousal. Due to the lower physiology state during the torpor, it is a challenge to detect neural activities in vivo on freely behaving mice. Here, we introduced a multichannel microelectrode array (MEA) for real-time detection of local field potential (LFP) and action potential (spike) in the SCN in induced torpor mice. Meanwhile, core body temperature and behaviors of mice were recorded for further analysis. Platinum nanoparticles (PtNPs) and Nafion membrane modified MEA has a lower impedance (16.58 ± 3.93 kΩ) and higher signal-to-noise ratio (S/N = 6.1). We found that from torpor to arousal, the proportion of theta frequency bands of LFPs increased, spike firing rates rapidly increased. These results could all be characteristic information of arousal, supported by the microscopic neural activity promoting arousal in mice. MEA displayed real-time dynamic changes of neuronal activities in the SCN, which was more helpful to analyze and understand neural mechanisms of torpor and arousal. Our study provided a factual basis for the neural state in SCN of induced non-hibernating animals, which was helpful for the application of clinics and spaceflight.

Keywords: 5′AMP induced torpor; arousal; electrophysiology; implanted MEA; suprachiasmatic nucleus.